The head of a mammalian sperm is...

Massive amount of yolk present in the vegetal region of the egg makes an egg:

In the diagram of a section of a Graafian follicle,different parts are indicated by alphabets; choose the answer in which these alphabets have been correctly matched with the parts they indicate.

Primary spermatocyte differs from spermatogonium in

Nebenkern is a part of

During spermatogenesis,the process of meiosis-$II$ occurs during which of the following transitions?